My mom got 800mb over her 200mb plan, I can't figure out why
iTunes Match says its not on for cellular, no apps, just turned airplane off and a few minutes later its slams these messages, no speed test either

Edit- read whole thing before starting... Answer may lie in my last suggestion.

Turn off wifi

Reset cellular data usage

View usage after 10 seconds, and again after 20. Is it climbing?

Yes - start turning off things until it stops. Then you've found the culprit.

Begin with iCloud. Simply turn off contacts, then calendars, then safari... Checking data after each one. After you've turned all those off, if the problem continues, move on to exchange accounts. Disable mail, check. Disable calendars, check.

Oh - and if sent data > received data you may have a mail message stuck in your outbox. Restoring to a new device with IMAP or POP accounts does NOT always restore the outgoing SMTP server password. No password, and outgoing mail gets stuck in a loop on the phone. Hope this helps.

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